Method and device for use in minimally invasive placement of space-occupying intragastric devices

ABSTRACT

A space occupying device for deployment within a patient&#39;s stomach and methods of deploying and removing the device. The device includes an expandable member and fasteners, such as sutures, that extend to least partially through the patient&#39;s stomach wall, and that anchor the device with the patient&#39;s stomach. The device can be deployed and/or removed through transesophageal approaches and/or through a combination of transesophageal and transabdominal approaches.

This application claims benefit of priority under 35 U.S.C. § 119(e) ofU.S. Provisional Application No. 60/245,466, filed Nov. 3, 2000, whichis incorporated herein in its entirety.

BACKGROUND OF THE INVENTION

The present invention relates generally to medical apparatus and methodsand more particularly to devices and methods for the insertion andsecuring of expandable devices and the like into a patient's bodycavity, such as the stomach, intestine or gastrointestinal track forpurposes of taking up space to provide the patient with a feeling ofsatiety or fullness. These devices may also be removed once they haveserved their purpose, e.g., the patient has lost the directed or desiredamount of weight.

Currently, in cases of severe obesity, patients may undergo severaltypes of surgery either to tie off or staple portions of the large orsmall intestine or stomach, and/or to bypass portions of the same toreduce the amount of food desired by the patient, and the amountabsorbed by the intestinal track. Procedures such as laparoscopicbanding, where a device is used to “tie off” or constrict a portion ofthe stomach, or the placement of intragastric balloons can also achievethese results.

Endoscopic procedures that have been used to assist weight loss havebeen primarily focused on the placement of a balloon or other spaceoccupying device in the patient's stomach to fill portions of thestomach to provide the patient with the feeling of fullness, therebyreducing food intake. To accomplish these procedures, an endoscope isutilized to guide the balloon through the patient's mouth and down theesophagus to the stomach. Usually these procedures have allowedplacement of the device for 6-12 months, and are coupled with counselingand other types of psychological support.

In the case of laparoscopic banding or balloon placement, however,several complications can arise that make these procedures, in theirpresent form, clinically suboptimal. The surgical interventionsdescribed above require the patient to submit to an intervention undergeneral anesthesia, and can require large incisions and lengthy recoverytime. The less invasive procedures described above, although clinicallyefficacious in many cases, suffer from complications ranging fromdeflation of the devices resulting in unsustained weight loss, stomacherosion, bowel obstruction and even death.

Many of these described problems have stemmed from the fact that thedevices were not robust enough to sustain long term implantation, andthat they were implanted in such a manner as to remain unattached orfree-floating within the stomach. Further, due to the caustic nature ofstomach acids and other factors, many of the implants deflated andmigrated into the intestine, causing bowel obstructions and in somecases death. Also, many devices were not well designed for removal,leading to additional technical difficulties for the clinician.

Additionally, current balloon designs do not allow for the adjustment ofballoon size, days or months after initial implantation. This featurewould be useful to adjust performance and/or reliability, which may beuseful over time.

Because of the limited success of several of these procedures, thereremains a need for improved devices and methods for more effective, lessinvasive, weight loss.

SUMMARY OF THE INVENTION

The present invention meets these and other needs by providing forimproved methods and apparatus for implantation and removal of spaceoccupying devices into the gastrointestinal system of a patient,provides for methods and devices for implantation in the stomach of apatient that can be deployed in a minimally invasive manner throughclinically established techniques, such as the technique used during apercutaneous endoscopic gastrostomy (PEG) tube placement that includestransesophageal endoscopy. The invention allows greater access toprocedures and devices by patients who might not otherwise be treatedsurgically as “morbidly obese” (at or above a Body Mass Index (BMI) of40 kg/m3), but who may just be moderately obese or overweight (BMI ofbetween 25 to 40 kg/m3). In addition, patients who require more invasivesurgery for an unrelated ailment, may need a minimally invasive way tolose the weight prior to their more invasive procedure, thereby reducingthe risks associated with general anesthesia, or otherwise enabling themore invasive procedure.

In one aspect of the invention an expandable device is provided that canbe inserted into the stomach of a patient. Its position is maintainedwithin the stomach by anchoring or otherwise fixing the device to thestomach wall of the patient.

In another aspect, the invention provides an expandable device thatconsists of two portions, an inner portion and an outer portion, theinner portion being able to maintain its shape, regardless of theintegrity of the outer portion.

In yet another aspect the invention provides for an expandable balloondevice that maintains its expanded shape and desired volume, independentof any small leaks that may develop over time. Furthermore, in the eventof leaks, the present invention prevents against migration orcontamination to the patient with the contents of the inflated volume.

The present invention also provides for means by which the volume of thespace occupying device can be adjusted in-situ, to change the size ofthe device after implantation.

The present invention to provide tools and methods for removal of theexpandable devices, e.g., once the patient has lost the desired amountof weight, or if it is necessary to remove the device for other reasons.The present invention further provides for features that allow theplacement and integrity of the space occupying device to be monitored bythe physician after implantation using minimally invasive imagingtechniques such as x-ray or ultrasound.

More particularly, in an embodiment of the invention an inflatable orotherwise expandable space occupying device is provided that can bedelivered or otherwise deployed through the patient's mouth in atransesophageal procedure into the patient's stomach. The deviceincludes an expandable member with one or more fasteners securedthereto. The fasteners are configured such that portions of thefasteners extend at least partially through the patient's stomach wall,thereby maintaining the device within the patient's stomach, but do notextend external to the patient's body. In one embodiment, sutures areused for fastening the device to the patient's stomach wall.

The expandable member may be constructed of a composite material toachieve desirable surface characteristics and is preferably visibleunder x-ray. In addition, the device of the present invention may havesurface features, such as a flange, beads, loops, and/or tabs tofacilitate manipulation, deflation and/or removal of the device.

The invention also provides for methods and apparatus for adjusting thevolume of the device while it is maintained in the deployed condition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-6 shows a method of placement of the space occupying device ofthe present invention; with FIG. 1 illustrating an endoscope deployed inthe patient's stomach and an external incision typical for performing agastrostomy procedure; FIG. 2 illustrating a snare introduced throughthe endoscope of FIG. 1 and snaring a guidewire introduced through aneedle cannula; FIGS. 3 and 4 illustrating the guidewires being advancedout of the patient's mouth and being fastened to a space occupyingdevice according to the present invention; FIG. 5 illustrating thedevice having been pulled into the patient's stomach and an endoscopereinserted; and FIG. 6 illustrating the device anchored with thepatient's stomach;

FIG. 7 shows a deployed space occupying device of the present invention,having beads incorporated into an inflated member of the device to aidin grasping and/or deflation of the device;

FIG. 8 shows a method of deflating a space occupying device according tothe present invention, illustrating a snare positioned to grasp a beadlocated on a inflated member of the device;

FIG. 9 shows an expanded view of the bead and snare of FIG. 8, withparts broken away;

FIGS. 10-11 show a space occupying device according to the presentinvention having tabs adhered to the inflated member of the device toaid in grasping and/or deflating the device, with FIG. 11 illustrating across-sectional view with parts broken away of a tab adhered to theinflated member;

FIG. 12 shows a space occupying device according to the presentinvention having a band extending around the device to aid in graspingand manipulating the device;

FIG. 13 shows a method of removing the space occupying device of FIG.11, illustrating a snare used to grasp a tab on the device;

FIG. 14 shows a method of releasing a space occupying device accordingto the present invention from an anchored position in the patient'sstomach, illustrating a cutting tool positioned to sever a sutureanchoring the device with the patient's stomach;

FIG. 15 shows a space occupying device according to an embodiment of theinvention, including a valve and removal flange features;

FIG. 16 shows the device of FIG. 15 deployed in a patient's stomach,with a grasping tool positioned to grasp the flange;

FIG. 17 shows a detailed view of the valve configuration of the deviceof FIG. 15, with parts broken away, and an inflation needle positionedto engage the valve;

FIGS. 18A-18C show a method of making a space occupying device accordingto the present invention having another valve configuration, with FIG.18C illustrating a cross-section of FIG. 18B taken along line 18C-18C;

FIG. 19 shows a space occupying device of the present invention havingyet another valve configuration;

FIG. 20 shows a space occupying device according to another embodimentof the present invention having a toroidal configuration and a graspingloop for grasping and manipulating the device;

FIG. 21 shows a space occupying device according to yet anotherembodiment of the invention, illustrating the device expanded with anexpanding element of predetermined shape;

FIG. 22 shows a space occupying device according to yet anotherembodiment of the invention, illustrating the device expanded with arandomly shaped expanding element according to the present inventiondeployed in a patient's stomach;

FIG. 23 shows a space occupying device of the present inventionconnected to a subcutaneous port for modifying the volume of the devicein situ;

FIG. 24 shows a space occupying device according to another embodimentof the invention having a deployable expanding element incorporated intothe device;

FIG. 25 shows a space occupying device according to the presentinvention having a radiopaque grid or film placed on a surface of thedevice;

FIG. 26 illustrates a cross-sectional view space occupying deviceaccording to an embodiment of the present invention having internalbaffles within the device to control flow and distribution of internalinflation media;

FIGS. 27A-27B illustrate a space occupying device according to thepresent invention having a particular valve and docking construction toallow for in situ modification of the space occupying device volume;with FIGS. 27A and 27B illustrating side and top views of the valve;

FIG. 27C shows an endoscope-docking device assembly, the docking deviceconfigured to receive the valve of FIGS. 27A;

FIGS. 27D-27F show cross-sectional views of the assembly of FIG. 27Ctaken along lines 27D-27D, 27E-27E and 27F-27F, respectively; and

FIGS. 28A-28E show another method of placement of the space occupyingdevice of the present invention, with FIG. 28A illustrating a needleadvanced into a patient's stomach and one end of a piece of sutureadvanced into the stomach; FIG. 28B illustrating the needle partiallywithdrawn from the patient; FIGS. 28C and 28D illustrating the needleadvanced back into a patient's stomach at a different angle and theopposite end of the piece of suture being advanced into the stomach;FIG. 28E illustrating both ends of the piece of suture advanced out ofthe patient's stomach and through the esophagus; and

FIG. 28F illustrating the device anchored within the stomach by thesuture.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides for space occupying devices deployable ina patient's stomach, and methods of deployment, manipulation and removalof such devices.

Method of Deployment and Removal

A space occupying device according to the present invention can bedeployed into the patient's stomach in a variety of ways, includingpassing the device through the mouth and down the throat with the aid ofan endoscope or like device (transesophageal approach), or by performingprocedure similar to a percutaneous gastrostomy procedure and gastricfistula to pass the device through the stomach wall and into thestomach. In a preferred method, a combination of both these approachesis taken, as further described herein. Prior to undergoing thisprocedure, the patient is preferably sedated to lessen the patient'sdiscomfort, and a local anesthetic may also be applied at the site ofthe puncture or incision.

FIGS. 1-6 illustrate in further detail an inventive method of deployinga device of the present invention. FIG. 1 shows a conventionalfiberoptic flexible endoscope 10 that has been advanced down a patient'sthroat and esophagus to an appropriate area 11 within the stomach (S),the distal end of the endoscope being located at or near the wall of thestomach (SW) at the desired location for performing a percutaneousgastrostomy procedure and, ultimately, for anchoring the device of thepresent invention. The endoscope 10 is then illuminated against thestomach wall (SW) such that the endoscope operator may observe lightfrom the outside of the patient's stomach through the stomach wall (SW)at incision point 12. The location may also be externally palpated andthe endoscope operator can observe the resulting indentation via theendoscope. An incision 20 is then made at incision point 12 and extendsto the fascia. Incision 20 as shown is approximately 1 cm. It is alsopossible to make only a puncture to a similar depth withoutnecessitating a scalpel incision, and still deploy the device inaccordance with the invention.

At this point, some of the components typically found in a standard PEGtube set can be employed to assist in the placement of the device of thepresent invention within the stomach. A typical PEG tube kit, such asthe PONSKY “Pull” PEG Kit (C. R. Bard, Inc., Billerica, Mass.),includes, e.g., a needle cannula with stylet, and a guidewire. Variouscomponents of this kit can be employed in placement of the device of thepresent invention as follows: at the point of incision 20, needlecannula 21 with stylet 22 are inserted through the incision, across theanterior stomach wall (SW) and into the stomach (S), as shown in FIG. 2.FIG. 3 further depicts the placement of snare device 30 through thelumen of endoscope 10, while the endoscope is directed toward needlecannula 21.

At this point in the procedure, the physician removes the stylet 22 fromneedle cannula 21, and inserts guidewire 23 through the lumen of needlecannula 21. The physician then snares guidewire 23 with snare 30, underdirect vision via endoscope 10, and tightens the snare to pull on theguidewire. With the snare in the tightened position, endoscope 10 isremoved from the patient's esophagus, thereby pulling guidewire 23 outof the stomach, through the esophagus and out the patient's mouth (M).Guidewire 23 is looped at its distal end (L) such that the looped end ispositioned outside the patient's mouth (M) once the snaring procedure iscomplete.

In a preferred method of the present invention, two guidewires areemployed and the described guidewire placement and snaring procedure isrepeated such that two guidewires 23, 23 are placed through the stomachwall (SW) and the looped ends (L) of each are positioned outside thepatient's mouth (M), as depicted in FIG. 3. Also, the two gastrostomiesthrough the stomach wall (SW) are preferably separated by approximatelya 1 cm distance.

FIG. 4 shows placement of the space occupying device 70 of the presentinvention, described in further detail below, over guidewires 23, 23.One or more sutures 71 are attached to space occupying device 70, andare threaded through the loops (L) of guidewires 23, 23. As depicted,space occupying device 70 includes a releasably attached inflator needle73 and inflator tube 74, including an inflator 75 to inflate or expandthe space occupying device 70, once it is placed. Alternatively, thespace occupying device can be provided pre-assembled with a sharppointed needle (not shown), i.e., of a kind typically used for injectionof a compound into a patient, which is connected by flexible tubing to asyringe that can be activated to inflate the device. Alternatively, thedevice can be inflated using a compressed gas system. For example, theinflator tube can be connected to a canister of compressed gas, througha pressure regulator. In this manner the fill rate and balloon pressurecan be better controlled. In most cases, a final inflated pressure ofabout 1-2 psi is desirable.

FIG. 5 illustrates insertion of space occupying device 70 into thepatient's stomach by pulling guidewires 23, 23 back through the stomachwall (SW), such that the sutures 71, 71 follow the guidewires 23 downthe esophagus into the stomach, and out through the incision 20, orother puncture(s) as applicable. This portion of the procedure may beperformed under direct vision by reinserting fiber optic scope 10 andfollowing space occupying device 70 down the esophagus. The sutures canoptionally be marked at intervals, e.g., by the use of paint, dye, glue,metallic coatings, and the like, to aid the physician in monitoring theprogression of the device deployment. This method provides for facileinstallation of the device, due to the pulling force transmitted by theguidewires to the device, as opposed to conventional methods ofinserting such devices which typically require a pushing force to pushthe device down the esophagus and into the stomach. Such pushing methodsoffer less control over the direction of the distal end of the deviceand can lead to the device getting caught up or snagged in theesophageal tract as it is being inserted. In many cases involving suchpushing methods of insertion, sheaths or other similar protectivedevices are installed onto the device to facilitate navigation of theesophageal tract. In the present method, such sheaths are unnecessary.

Optionally, space occupying device 70 can further include safety leash76 looped through eyelet 77 secured to the device, as depicted in FIGS.4 and 5. The leash can be formed of e.g., a suture material. Theprovision of leash 76 allows for emergency retrieval of the device fromthe esophagus during deployment of the device. Such retrieval capabilityis desirable, for example, where a patient begins choking and it becomesnecessary to quickly remove the device from the patient's esophagus.

FIG. 6 depicts the process of securing the sutures 71 through thestomach wall (SW), through the peritoneal cavity by tying a subcutaneousknot to anchor the space occupying device against the stomach wall (SW)prior to inflation or expansion. FIG. 6 further shows the anatomy of thestomach wall (SW) and the intervening fascia and adipose layers throughwhich the guidewires 23 are placed. The stomach wall (SW) consists of amuscular layer (including oblique, circular and longitudinal musclefibers) (MF), a mucosal and sub-mucosal layer ML, and gastric glands andpits on the inside surface (GG). Fascia layer (FL) surrounds the outsideof stomach wall (SW). The knot can then be pushed down under thesubcutaneous fat, and can remain at or even within fascia layer (FL).Incision 20 or similar opening puncture is closed by establishedprocedures (e.g. suture, staple or other closure procedure).

Various materials known in the art are suitable for use as sutures,including polypropylene, polyester, and nylon, as well aspolytetrafluroethylene (PTFE) suture, such as GORETEX® suture. Theinvention also contemplates the use of other conventional fasteners forsecuring the device to the stomach wall, including, e.g., endoscopicstaplers, cable-ties and the like, and shape memory or superelasticclips that incorporate into tissue, as long as such fasteners arecapable of being deployed such that portions of the fasteners extend atleast partially through the patient's stomach wall, but they are notrequired to extend all the way through the patient's abdomen to maintainthe device in place, i.e., they do not extend external to the patient'sbody. By at least partially extending through the stomach wall it ismeant that such fasteners extend into at least one of the tissue layersthat comprise the stomach wall, including the inside surface (GG),mucosal and sub-mucosal layer (ML), and muscle layer (MF).

It is also within the scope of the present invention to employ a knotmarker or other palpable element such as a sterile bead, that willassist during removal of the device. In particular, the physician willbe able to palpate the point at which the space occupying device isanchored prior to puncturing the inflated device or otherwise excisingthe knot location. This palpable element may also be used to confirm thelocation of the anchor physically without x-ray, to make sure the devicehas not migrated during the therapeutic life of the space occupyingdevice. The marker can be, for example, a surgical pledget or buttonthrough which the sutures are tied off. Knot markers can include two ormore suture holes radially spaced around a center deflation hole. Thesutures can be passed through the suture holes and tied off. Thedeflation hole can aid in a methods of deflating the device, as furtherdescribed herein. These knot markers may also act as strain reliefmechanisms as further discussed below.

Once anchored, space occupying device 70 is then inflated, as seen inFIG. 7, and inflation needle and inflator tube 74 are then withdrawnfrom the patient's stomach out the patient's mouth, leaving the spaceoccupying device 70, anchored to the stomach wall (SW). The patient canthen be monitored over time to confirm weight loss. The area of thestomach to which the space occupying device is secured may be varieddepending on the placement that is most advantageous to the patient'sweight loss, or feeling of satiety, relating to achieving weight loss.In some cases, it is preferable to place the device at the fundus of thestomach, close to the esophageal orifice.

Once the desired weight loss has been achieved, it is desirable thatspace occupying device 70 be easily collapsed and removed from thepatient's stomach. During the removal procedure, a standard endoscope10, is deployed down the patient's esophagus to view space occupyingdevice 70 directly. In addition to the scope, a scissor tool or grasperis deployed therewith to grasp or otherwise cut the space occupyingdevice to steady it and/or deflate it in preparation for removal. Thegrasping of the space occupying device 70 can be further facilitated bycertain surface characteristics of the device as further describedherein.

One advantageous method of deflating the device involves inserting aneedle or other sharp object directly into the stomach from the stomachexterior at or near the anchor location of the device. Using theexternal scar of the gastrostomy procedure as a guide, the generallocation of the anchor point of device can be fairly well approximated.In the case of, e.g., a tie-off button, the button can be palpated andthe center of the button, which generally corresponds to the anchorpoint, can be readily ascertained. The deflation needle can then beinserted through the center of the button to pierce and deflate theballoon.

Once space occupying device 70 has been deflated or otherwisecontracted, a percutaneous stick or incision can be made externallythrough the abdominal wall (AW) to facilitate the release of the knotsecured earlier in the procedure during anchoring. After the anchoringmechanism has been released and space occupying device 70 has beendeflated or otherwise contracted, the entire device can be removed fromthe patient's stomach using, e.g., an endoscope and grasping device. Theskin puncture or incision is then closed.

Alternatively, one or more steps of deflating the balloon, cutting orotherwise severing the anchoring sutures, and removing the device can beaccomplished by means of a snare and various beads or tabs or other likeprotrusions attached to or incorporated directly into the balloonitself. FIG. 8 depicts device 70 having deflation bead 81 extending fromthe surface of the device, with snare 90 positioned to grasp the bead.As seen in FIG. 9, the bead is secured to loop 82, formed of a suturematerial, which itself spans the wall of the inflatable member. When thebead is grasped by the snare and pulled away from the balloon, loop 82is also pulled away from the balloon. This causes a tear or a rip in theinflatable member at the site of insertion of the loop, resulting indeflation of the balloon.

Another method for deflating the device is illustrated in FIG. 19, whichdepicts a balloon member having a retractable deflation valve 52 withsuture loop 53 attached to top portion of the valve and extending fromthe balloon surface. A valve of this configuration is in a sealed orclosed position when the valve body is pushed down and seated into aretracted position within the balloon. Typically, the balloon will beinflated by other means. When the deflation valve body is pulled upward,by, for example, pulling on suture loop 53, the valve opens. An graspingtool can be used to grasp and pull suture loop 53, thus opening thevalve and deflating the balloon.

The device of the present invention can also include beads and/or sutureloops and/or tabs that are attached to or are integral with balloonmember, and which can be used to remove the device from the patient'sstomach. For example, FIG. 7 illustrates device 70 having grasping beads85 that are secured to and extend from the balloon surface, and FIG. 11shows a device having tabs 91 secured to the balloon surface. Asdepicted in FIG. 13, snare 90 can be used to grasp tab 91 and cansimilarly be used to grasp beads 85. Once the balloon is deflated andthe sutures cut or otherwise severed, the snare can be used to pull thedevice from the patient's stomach. As depicted in FIG. 13, device 70 isin a deflated condition, but the grasping of tab 91, or a bead or sutureloop, can also be accomplished when the device is in the inflatedcondition.

Another method for removing the device is shown in FIG. 14, whichillustrates a device where suture 71 extends around the circumference ofthe balloon, and is threaded through guides 88 to retain the position ofthe suture relative to the balloon. A cutting tool (CT) is deployedthrough endoscope 10 to cut or sever the suture. With the suturesevered, the device is then freed for removal from its anchoredposition.

FIGS. 28A-28F illustrate another method according to the presentinvention of placing a space-occupying device that does not require apercutaneous endoscopic gastrostomy or like procedure. Rather, as shownin FIG. 28A, needle 92 is positioned externally of the patient's stomachand inserted at a first angle through the patient's stomach wall andinto the stomach itself. Suture 71 is then fed through the needle untila first end portion 78 of the suture is deposited into the stomach. Theneedle is then partially withdrawn from the stomach such that the needletip either remains within the stomach wall itself or at least remainswithin the peritoneal cavity is not withdrawn into the external layer ofthe abdominal wall, as seen in FIG. 28B. The needle is then advanced ata second angle into the stomach and the opposite end portion 79 of thesuture is advanced through the needle and deposited into the patient'sstomach, as shown in FIGS. 28C-28D. At this point the needle can becompletely withdrawn, and the two suture ends can be grasped by agrasping tool and pulled out through the patient's esophagus, throat andmouth, as seen in FIG. 28E and much as described above with respect toguidewires 23.

A space occupying device is then secured to one end of the suture (notshown) and by then pulling on the opposite end of the suture the devicecan be pulled through the patient's mouth, throat and esophagus forplacement in the stomach. It is desirable to include a guide (not shown)on the device through with the opposite end of the suture can bethreaded. Once the device is placed the suture can then be secured tothe guide, such as by tying off the suture to the guide, or by otherknown means, in order to anchor the device in place, as shown in FIG.28F.

This method is advantageous in that it offers an even more minimallyinvasive approach than using a percutaneous endoscopic gastrostomytechnique, as there is only a single puncture site required. In avariation of the method, guiding suture 69 is also introduced into thepatient's stomach using a needle, and a portion of this guiding sutureis likewise pulled via an endoscope out of the patient's mouth andsecured to the device. By exerting a pulling force on the portion of theguiding suture remaining external to the patient's abdomen, the devicecan be pulled into position and tied-down. The guiding wire can be cutor otherwise released from the device.

The device can also be placed using a method that relies on apredominantly endoscopic approach without requiring a percutaneousendoscopic gastrostomy or even accessing the stomach from the patient'sexterior. This method employs an endoscopic suturing device, such as theENDOCINCH™ endoscopic suturing device (C. R. Bard, Inc., Billerica,Mass.). The device includes a capsule and a needle that is advanced viaan endoscope down a patient's throat to a desired location within thepatient's stomach. The needle includes loaded suture with a suture tag.The device includes a capsule having an opening that is placed againstthe stomach tissue, and a vacuum is applied to bring a fold of tissueinto a chamber of the capsule. The needle is then advanced through thefold, deploying the suture and suture tag, which is captured in the endcap of the capsule. The device is then withdrawn, leaving suture passingthrough the stomach tissue and two free ends of the suture running outof the patient's mouth. The device of the invention can then be attachedand/or threaded onto the suture ends and advanced into the patient'sstomach. For example, one end can be tied to device and the other endused to pull the device down the patient's esophagus, as describedabove, and then tied off. Alternatively, both ends of the sutures can bethreaded through guides on the device, and the device can be pushed downthe patient's esophagus and into place using a delivery catheter orsheath or the like. In either method, the sutures can be tied down,securing the device in place, using knot pushers known in the art, suchas, e.g., those described in U.S. Pat. Nos. 5,391,176 and 5,527,323,each of which is incorporated herein in its entirety. Alternatively, theendoscopic suturing steps can be repeated to provide multiple anchoringsites in the stomach tissue for anchoring the device.

Expandable Devices

Reference has been made throughout the previous section, to a spaceoccupying device 70. The following descriptions are intended to adddetail and further description to the composition and structure of suchspace occupying device and other attendant features. The space occupyingdevice contemplated by the present invention will preferably have thecharacteristics of a low profile insertion diameter, capable ofexpanding to a larger diameter to fill the stomach with the requiredvolume to achieve the feeling of fullness, or satiety, in the subjectpatient. There are various embodiments that fulfill these requirements,and that are the subject of the present invention.

As described, one embodiment of the space occupying device is anexpandable device comprising an inflatable balloon as depicted in FIG.15. Outer member 140 may be formed of a polymeric material such assilicone, polyethylene, vinyl, polyurethane, urethane or the like, or amaterial such as mylar, aluminized mylar, neoprene, non-polymeric orthin walled metal materials or other similar materials. Outer member 140is formed of two sheets of material that are laminated together leavinga seam or flange 141.

Flange 141 may be used as a mechanism to assist in removal of the spaceoccupying device as shown in FIG. 16. For removal, endoscope 10 isinserted using the transesophageal approach into the stomach to theproximity of the implanted space occupying device, through which agrasping tool (GT), such as a laparoscopic grasper or biopsy tool suchthat when actuated, can engage the flange 141 such that once the spaceoccupying device is deflated and any anchoring released, the graspingtool (GT) can be pulled along with the scope thereby extracting thespace occupying device.

While the space occupying device is shown with the flange portionexternal of the sphere, it is also contemplated by the present inventionthat the flange may extend inwardly of the space occupying device,thereby providing a smooth exterior, or the space occupying device maybe formed as to have no seam whatsoever, but merely an orifice for thevalve mechanism. In addition, it is also contemplated by the presentinvention that the flange may be asymmetric, i.e. only present around apartial circumference of the space occupying device to facilitategrasping, but to minimize any erosive effect on the portion of thestomach wall (SW) with which the space occupying device comes in contactonce secured at the anchoring point (AP). For example, the durometer ormaterial at the anchoring point (AP) may be softer than that used in theother portions of the space occupying device.

In a preferred embodiment, the balloon is formed of a urethane interiorand a silicone exterior. The urethane provides a durability to theballoon for resisting undesirable rupture or leakage and the siliconeexterior provides for a smoothness, and conformability to avoidunnecessary trauma or irritation to the stomach lining.

In another embodiment of the balloon, the balloon is formed of acomposite of silicone, aluminized polyester film, and polyethylene. Inthis embodiment, the space occupying device is formed by heat-sealingsheets of mylar/polyethylene composite. The seam is then trimmed to aminimum size and a valve attached. The assembly is then dipped in roomtemperature vulcanizing (RTV) liquid silicone which, once cured, willleave a smooth surface, which may or may not have a palpable seam.Alternatively, the space occupying device can be rotated as the siliconecures, to allow for a more consistent coating to form.

A variety of sizes and shapes of the balloon are contemplated by theinvention, and it is to be appreciated that one skilled in the art wouldbe competent to choose a particular shape and size according to theparticular application. The balloon can be, for example, spherical orellipsoidal or another suitable shape. In the case of an ellipsoidalballoon, a preferred method of anchoring such a balloon is along thelonger axis of the balloon. Balloon volumes can vary, but a typicalvolume is approximately 500 cubic centimeters (cc).

The deflation, grasping, and suture beads described above can all beformed of a variety of materials, including metals or plastics, providedthey are inert, biocompatible, and capable of withstanding acidicstomach conditions, and exposure to consumed food and liquids. It isdesirable that the beads be formed of a moldable plastic, such aspolycarbonate, polyethylene, or polypropylene. The beads can also beformed of a radiopaque material, such as a metal, or a plasticcontaining radiopaque material, e.g., barium sulfate (BaSO4), as an aidin monitoring placement of the device as further described herein.

For deflation beads, the beads can be located on and secured to theballoon wall as shown in detail in FIG. 9, using loop 82. The loop canbe, for example, formed of a piece of suture passed through the balloonwall and tied off, and then again passed through a through hole in thebead and again tied off or otherwise secured. Adhesive 83, for example,a silicone glue, is applied to the balloon wall at the points where thesuture passes through the balloon wall, to preserve the integrity andinflatability of the balloon. As discussed, a tear in the balloon wallcan be caused by applying a pulling force on the grasped bead. This samebead formation can also be used to facilitate grasping and removing adevice according to the invention, once the anchoring system, if used,has been released from the stomach wall site.

Alternatively, a suture loop extending from the balloon surface can beformed in a like manner, with the exception that a bead is not included.This suture loop can likewise be easily grasped, e.g., by a graspingtool advanced through an endoscope, and used to facilitate manipulationof the device.

FIG. 11 shows a device having tab 91 secured to the balloon surfacewhich likewise serves as a means for grasping and manipulating theballoon. The tab 91 can be secured to the balloon wall by an adhesive,with a portion of the tab extending from the balloon surface forgrasping. In a preferred embodiment, the balloon is urethane with asilicone coating, as further described herein, and the patch is asilicone tab secured to the balloon with an adhesive such as RTVadhesive. By securing the patch to the outer surface of the balloon, theintegrity of the balloon wall is preserved.

Modification of the tab and corresponding attachment area of the ballooncan also be made to provide relative areas of strength or weakness inthe overall balloon surface. In particular, the patch system describedcan be configured such that it functions as a deflation mechanism. Asshown, tab 91 covers weakened portion 93 and strengthened portion 94 ofthe balloon wall. For example, by heat sealing the patch to the balloonwith heat source located on the balloon side, the patch is both securedto the balloon and the weakened portion of the balloon is simultaneouslyformed. The weakened portion can also be created by, scoring, etching orotherwise thinning the balloon wall. The strengthened portion can becreated by reinforcing, thickening, taping, or adhering additionalmaterial to the balloon surface. Such strengthening of sections of theballoon can also be accomplished with the combination with a tab, inorder to strengthen and/or enhance the structural integrity of theballoon. In the configuration shown in FIG. 12, the application of anupward force to patch 91 at the extended portion 95 will promote acontrolled tearing of the balloon wall at the point of least resistance,i.e., weakened portion 93. In this manner, the balloon can be deflated.In addition, the balloon may also be removed by further force on thesame grasped tab. In a preferred method where the tab is secured to theballoon by a heat sealing method, by adjusting the heat sealing pattern,the tab can be secured in such a manner that the formed weakened portionof the balloon will be susceptible to tearing, but other portions of thesecured tab will be predisposed to remaining attached to the balloon. Insuch a manner, grasping and pulling on the tab can rupture the balloonto cause deflation yet still allow for removal and manipulation of theballoon by the same grasped tab.

Patch 99 is provided to reinforce the balloon at the suture attachmentpoint, and to also provide for smoother surface at the suture attachmentpoint to lessen irritation to the stomach wall upon attachment. Thepatch can be secured to the balloon with an adhesive, like tab 91, andcan be formed of, e.g., urethane or other similar material, and canfurther have a silicone coating.

FIG. 12 depicts another embodiment of the invention that provides for agrasping feature. In this embodiment, band 96 extends around thecircumference of the balloon, and includes protrusions 97 that extendfrom the band for grasping and manipulating the balloon. The band can beformed of materials such as those described above for tab 91 and canlikewise be adhered to the balloon. The protrusions 97 can be of avariety of shapes. In the depicted embodiment, they are simply foldedportions of the band itself.

In an alternative embodiment of the device, device 60 can be of atoroidal configuration, as depicted in FIG. 20. This toroidalconfiguration can have a variety of annular cross-sectional shapes,including round, elliptical, and the like. The advantage of suchconfigurations is that the beads, guides, suture loops, and tabsdescribed above can be positioned along those areas the surface areas ofthe device that line the passageway through the center of device formedby the toroidal shape of the device. In this position, these beads,guides, loops, patches, etc. are kept away from the stomach tissue,which lessens the chance of stomach lining irritation and/or erosionsuch devices could cause when located on the outer diameter of thedevice. Also, the addition of such a passageway can also aid in thepassage of food through the stomach when the device is deployed,lessening the potential of the device to clog the patient's pylorus. Inaddition, as shown in FIG. 20, suture loops 62 can be secured to thedevice by passing the suture through the passageway and tying it offaround the device. These loops can be easily grabbed by a grasping toolto manipulate the device.

Other portions of a device according to the invention, such as a flange,if provided, or other additional materials, may operate or encompass astrain relief mechanism to accommodate and disperse the forcesaccompanying any movement of the device attendant due to, e.g., theeffects of stomach wall motion of the implanted device.

In particular, a strain relief mechanism functions to reduce strain onthe stomach wall at the suture points and to more evenly spread thestrain or forces extended on the stomach wall by the device over abroader area. One such strain relief mechanism comprises one or moresoft silicone cups, with the rim of the cup being adapted to pressagainst the inside of the stomach wall around the points of suture. Inaddition, a strain relief mechanism may also be applied against theexternal stomach wall, such as a strip of polypropylene mesh, or othercompliant material to provide a more secure means of attachment againstthe outer stomach wall. A pledget or tie-off button or similar devicemay also be used to accomplish the same effect, as is known in the art.

In addition, FIG. 26 illustrates a cross sectional view of a spaceoccupying device that incorporates internal baffle structures 201A and201B that are formed integrally with the outer member 140, or may be aseparate structure. Baffles 120A and 120B operate to distribute anyinternal inflation media within the space occupying device, therebydecreasing any discomfort to the patient caused by the weight andmovement of the device once anchored to the stomach wall. These baffledevices can be in the form of separate compartments, foam materials,gel-type materials or fibers, that can be inserted into the spaceoccupying device either pre- or post-deployment, depending on theinsertion profile desired.

As shown in FIG. 17, valve device 142 facilitates the expansion andcontraction of the space occupying device. Valve device 142 includesreception chamber 150 for receipt of an inflation needle 73, and havingchamber walls 143A and 143B molded into a single piece and glued orotherwise attached within the layers of outer member 140. The valvedevice may be affixed within space occupying device 70 in various ways,including gluing, threading, heat sealing or installation of a smallhose clamp to secure the valve body. Valve device 142 can, but need not,have dimensions including an overall width of 0.24″, and an overalllength of 0.65″. The reception chamber has a dimension of preferably0.070″ wide by 0.44″ in length, allowing for a portion of the valve tobe solid material, subject only to a puncture by a needle or other sharpinflation tool such as inflation needle 73.

As also discussed above, a pre-assembled sharp needle and syringe withcheck valve combination may be used to inflate the device. In addition,the valve employed in such a case can be a one-way valve known in theart that is self-closing upon removal of the needle. It is alsoadvantageous, in such cases, to include a cylindrically shaped valveguard (not shown) extending inwardly of the balloon at the valve site.This valve guard can be formed of a variety of materials, such as a hardplastic, and serves to avoid inadvertent puncturing of the balloon bythe sharp needle upon installation and deployment of the device.

Another method of forming the device with an integral valve is depictedin FIGS. 18A-18C. In this method complimentary sheets of balloonmaterial, such as urethane, are aligned and heat sealed together alongtheir perimeter, as depicted in FIG. 18A. The sheet configuration andheat sealing pattern yields valve portion 42 and anchor sutureattachment portion 43. The heat sealed unit is then inverted, asdepicted in FIGS. 18B-18C, and anchoring suture 71 is then heat sealedto anchoring suture attachment portion 43 of the formed balloon. Theformed valve of the balloon is self-closing upon removal of an inflationneedle after inflation.

Complications of prior art devices have included erosion or irritationof the stomach wall. These are overcome by the combination of elementspresent in the described invention, namely that the space occupyingdevice is not free to float about the stomach causing such damage, butis secured in a specific location where design features can minimizesuch complications. It is further contemplated by the present inventionthat the expandable member may be lined, or otherwise reinforced withthe same or different material to guard against leak or deflation, andalso to provide for a conformable outer surface, further decreasing theside effect of erosion. For example, the expandable member may be formedof silicone or another material having conformable, compliantcharacteristics, and be lined with a second material such as urethane,that has a low porosity to provide for longer inflation, but may be morerigid thereby increasing the risk of erosion.

Similarly, the expandable member may be formed of a lower porositymaterial, and then “dipped” or coated with a more compliant or pliablematerial to achieve a similar effect. It is also contemplated that thesame configuration can be achieved by placing one structure of onematerial inside the other structure of another material prior toexpansion.

Inflation/Expansion Media

The invention further provides an inflation or expansion media that isof low density and which also poses a low risk or toxicity to thepatient should the space occupying device become compromised, eitheraccidentally during deployment or residence within the stomach, orintentionally, due to rupture attendant to removal of the device. Aspace occupying device according to the invention can be inflated orexpanded with various media including, air, water (H2O), carbon dioxide,argon gas, helium or other inert gas, saline, certain slurries or otherviscous materials such as mineral oil (and combinations of the foregoingwith a mineral oil solution), glass beads, Perlite®, suture material(e.g. prolene, nylon or other space occupying material that can berendered sterile), and organic material, such as seeds (e.g. poppy,sesame, wheat, bean, pysillium), xanthum gum, and the like. Organicmaterial may pose less of a threat to the patient in a situation whererupture of the space occupying device may occur. The filling materialmay also include barium sulfate (BaSO4) or a similar agent so it can beseen on x-ray; or blue dye, such as methylene blue, such that thepatient would notice a change in urine color that would signify a leakor other break in the device barrier. In addition, if the mechanism forremoval requires deflation of the volume, it may be advantageous tointentionally rupture the space occupying device to assist removal.

Inflation/Expansion Elements

In it a further object of the invention to provide for an expansion orinflation media or element, that is independent of leaks or otherdisruption to the expandable member of the space occupying device. Thisaspect of the invention provides for an outer member coupled with aninner member, the inner member being adapted to operate independentlyfrom the outer member but intended to be enclosed by the outer member atthe point of initial deployment of the device. This inner member caninclude a variety of configurations such as an internal structure thatis a predetermined shape, a random shape, a manually actuated element,or a liner.

Predetermined Shape

In the embodiment depicted in FIG. 21 a formation is inserted into theexpandable member 140 through valve structure 142. Expandable member 140can be an expandable membrane, such as a balloon, or other expandablematerial such as graft material or other like covering. Inner member 170is preferably a resilient structure, such as a wire form made fromstainless steel, NiTi, Elgiloy, semi-rigid polymer, or other suchmaterial, that can be inserted into the expandable member yet maintainits shape independent of the integrity of the expandable member. Duringremoval, it is contemplated by the present invention that inner member170 can be removed by extraction through valve member 142, as in thecase of the more rigid members such as those made of metal or metalcomposites (e.g. NiTi, Elgiloy™ or stainless steel), or released intothe stomach cavity through disruption of the expandable member as in theless rigid, but filling inner members (e.g. suture, polymers).

Expandable Shell with Random Internal Structure

In another embodiment of the present invention, as shown in FIG. 22,inner member 171 comprises a random matrix of material, such as a linearstructure that has no predetermined shape but rather forms a randomlyarranged matrix upon introduction into the expandable member. Thismaterial can include wire made of a low profile NiTi wire, for example0.020″ diameter, braided suture material, or other material, such asstainless steel, Elgiloy™ alloy, or a pliable polymer matrix such aspolypropylene, polyethylene or polycarbonate. This inner member may beplaced in various ways, such as through a catheter device 172 by using apusher assembly 173, to deploy the inner member through valve 142, suchthat it reforms a random, space filling shape, within expandable member140. The present invention also contemplates that the random innermember may comprise a single strand of material to facilitate removal,or multiple strands or composites of a material to optimize the fillingof the space occupying device.

FIG. 22 depicts the deployment of inner member 171 via a transabdominalapproach once the space occupying device of the present invention issecured at the anchoring point (AP), but it is also within the scope ofthe present invention to deploy the inner member 171 via thetransesophageal approach. It is likewise within the scope of theinvention to deploy inner member 170 of FIG. 21 via the transabdominalapproach.

Expandable Shell with Manually Deployed Inner Structure

FIG. 24 illustrates a device having an inner member 180 that is insertedthrough valve opening 142 in a contracted configuration, and thenexpanded into an expanded configuration by manual manipulation by theplacing physician. The inner member includes a central shaft 181 towhich the distal ends of a manual expansion element 182 and cap DE bymeans of welding, gluing or other such attachment means. Movable shaft183, which has the ability to movably translate with regard to centralshaft 181 is placed coaxial around said central shaft 181. The proximalends of the manual expansion element are affixed to the movable shaft183, such that when said movable shaft 183 is advanced toward the pointDE, manual expansion elements 182 bow outwardly toward to effect anexpanded configuration coterminous with expandable member 140. Theproximal ends of said expansion elements 182, are similarly affixed in acoaxial configuration to movable shaft 183, such that the entireexpandable element 180 fits within expandable member 140.

Monitoring Placement

Once the space occupying device of the present invention has beenplaced, it is advantageous for the physician to be able to monitor theplacement and integrity of the device in a minimally invasive way. Toenable non-invasive monitoring, a feature of the present inventionincludes providing a radiopaque grid or pattern 190 permanently affixedto the space occupying device, as depicted in FIG. 25. The grid 190 maybe printed on or embedded within the layers of the outer member. In thisembodiment, a pattern is printed with an ink made of tungsten powder andglue, or thin strips of Copper, lead or stainless steel, and may measure0.10″×0.001″. These markings can then be affixed to the space occupyingdevice either internally, externally or laminated between the layers ofthe space occupying device during construction. In addition, the spaceoccupying device may be filled with inflation media that includes BaSO4.Alternatively, a small pressure transducer (not shown) with a radiotransmitter may be placed in the space occupying device to continuouslysend data to an external monitor (not shown). Under x-ray vision, thephysician can monitor both the placement (e.g. is the device stillproperly anchored against the stomach wall or other structure) and theintegrity (e.g. is the device still expanded) of the space occupyingdevice. This monitoring procedure may be done proactively, or as adiagnostic measure in the event a patient presents with symptomsrelating to loss of efficacy or physical complications.

In Situ Modification

An important feature of the present invention is the ability to modifythe volume of the space occupying device once it is implanted in thepatient's stomach. This is advantageous for a variety of reasons tomaximize the efficacy of the device for a particular patient. Duringimplantation, a patient may find that their hunger returns, or is morethan they would like. With a device of the present invention this can beaccomplished either through a transesophageal approach, or through theinstallation of a PEG tube at the site of anchor. FIGS. 27A and 27Billustrate one such embodiment, depicting a docking port 210 for a spaceoccupying device having a flange 141 and a valve with filling lumen 212.FIGS. 27C-27F illustrates a docking module 214 configured to fitcoaxially over the end of a conventional endoscope (ES). Docking module214 incorporates a snare housing 216 with a lumen to house a snaredevice (SD). In operation, for transesophageal access, the endoscope anddocking module are inserted down the patient's throat to the vicinity ofthe docking port 210. Snare device (SD) is used, under direct vision ofthe endoscope, to grasp gripping flange 141 and guide the docking module214 to mating engagement with docking port 210. Stops 217 can beincluded on the inner channel of the docking module to restrain theendoscope. An inflation device (not shown) can then be introducedthrough the endoscope and inserted into filling lumen 212 to furtherinflate, or deflate the space occupying device as desired. An optionalfeature of the docking module is an alignment target (not shown) thatcooperates with a point on the space occupying device, eitherelectronically, visually (i.e., a marker), or physically (i.e., a detentor other configuration), to assist in alignment of the docking modulewith the docking port.

In another inventive method, in situ modification of the device volumecan be adjusted through the use of an implanted subcutaneous port 175,placed in the arm, stomach or pectoral area of the patient, as depictedin FIG. 23. Typical ports used for drug delivery are the BARDPORT®implanted ports (Bard Access Systems, Salt Lake City, Utah) and theVORTEX™, TRIUMPH-1®, LIFEPORT® and INFUSE-A-PORT® implanted ports(Horizon Medical Products, Manchester, Ga.). For use in the presentinvention, such ports may be modified, according to ways known in theart, to provide a more durable septum to accommodate a lower gaugeneedle and a larger lumen catheter that are desirable for the moreefficient ingress or egress of air, gas or other inflation media into orfrom the device.

While certain embodiments have been illustrated and described, thosehaving ordinary skill in the art will appreciate that variousalternatives, modifications, and equivalents may be used and that theinvention is not intended to be limited to the specifics of theseembodiments, but rather is defined by the accompanying claims.

1. A method of anchoring a space occupying device within the stomach ofa patient comprising the steps of: introducing a space occupying deviceinto the patient's stomach wherein said space occupying device includesan expandable member having one or more fasteners attached thereto; and,fastening said device to the patient's stomach wall such that portionsof said fasteners extend at least partially through the patient'sstomach wall but do not extend externally of the patient's body.
 2. Themethod of claim 1 wherein said fasteners comprise one or more sutures.3. The method of claim 1 wherein said space occupying device isinflatable, and wherein the method further comprises the step ofinflating the device after fastening the device to the patient's stomachwall.